2.9% on $100 is $2.90...I know you laughing at yourself now.  But I have the same and you don't have to give your client your email address although that is a way your can do that.  

You can add a pay pal button to your website directly by getting the text code from within your paypal account after you log in.  It is really easy to do and paypal will help you complete the function while on the phone.  It takes your client from your website to their paypal site and they can securely pay anyway they wish to pay.  I have used this also with clients and all one-time clients.  Works well.